Someone know math and can help me on at least one of these so I know what to do

A) if $50000 is invested in a bank account that pays 9.3% of interest compounded on a six-monthly basis, how much money will be in the account after 3 and 12 years? b) if matusalen's father had put $2.0 in the bank when he was born and there, how long would matusalen have had to his death (969 years later) if the interest was 7% per year composed each month and weekly?

Mrs. blake's bill at a restaurant is $42.75. she wants to leave the waiter an 18% tip. how much will she pay in all, including the tip?

The scatter plot shows the number of animal cells clara examined in a laboratory in different months: plot ordered pairs 1, 20 and 2, 60 and 3,100 and 4, 140 and 5, 180 what is the approximate predicted number of animal cells clara examined in the 9th month?